DOMINANT, adjective [Latin , to rule; lord, master; a house; to overcome, to subdue.]
1. Ruling; prevailing; governing; predominant; as the dominant party, or faction.
2. In music, the dominant or sensible chord is that which is practiced on the dominant of the tone, and which introduces a perfect cadence. Every perfect major chord becomes a dominant chord, as soon as the seventh minor is added to it.
DOMINANT, noun In music, of the three notes essential to the tone, the dominant is that which is a fifth from the tonic.